Seok Hyun Kim

Personal Information Exposure on Social Network Service

ABSTRACT This paper presents result of researching personal information exposure of Korean twitter and facebook users. Personally identifiable information such as e-mail and phone numer is expo sed in the accounts less than 1%. However there are many cases that a person is identified by non personally identifiabl e information. For example, 350 thousands accounts are distinguished with other accounts because its name is unique. U sing combination of information such as name and high school, we can distinguish 2.97 millions accounts. We also found 170 thousands account pairs that are candidate of one users’ own account. Linkability between two accounts in two different doma ins means that the person is identified. Currently, only personally identifiable information is protected by policy. Thi s paper shows that the policy has limited effects under the circumstances that a person can be identified by non personally identifiable information and the account linking is possible.Keywords: SNS, Pricacy, Personal Information, K-Anonymity, Re-identification